Lost vet Fionnula Flanagan and Vampire Diaries alumna Mia Kirshner have been added to the cast of Syfy’s upcoming series Defiance.

Set in a dystopian future, the drama finds humans and aliens coexisting on a war-ravaged Earth that has been transformed by terra-forming machines.

Per Deadline, Flanagan joins as the popular ex-mayor of Defiance (the titular town), who now acts as a mentor to her successor, played by Julie Benz (Dexter). Kirshner, meanwhile, will play the city’s “self-assured” madam.

Grant Bowler (True Blood) was previously cast as the series’ lead, the Chief Lawkeeper in the aforementioned boomtown, with Jaime Murray (Ringer) playing a member of an elite alien race.

Ready for more of today’s TV dish? Well…

• Rebecca Mader has nabbed a juicy guest spot in White Collar‘s upcoming fourth season. Per TVGuide.com, the Lost alumna will play Abigail, a con woman who blackmails Neal into helping with her latest heist — but that’s not all. Mader’s Collar gal will also attempt to seduce Diana, who is working undercover to take down the crookette.

• Comedy Central will air a Between Two Ferns special on May 6 before the Comedy Awards, funnyman Scott Aukerman announced Monday on his “Comedy Bang Bang” podcast. The half-hour televised installment of the web series will feature Hangover star Zach Galifianakis interviewing 30 Rock‘s Tina Fey, Daily Show‘s Jon Stewart and businessman Richard Branson.